Cylinder Block Assembly: Description and Operation
DESCRIPTION
The engine block (1) is made from cast iron. The crankshaft is supported by five main bearings. The thrust bearings are attached to the center upper main bearing. The cylinder block has four piston cooling jets located under the main bearing shells. The cylinders are formed directly into the engine block and are divided into three size categories. Special channels formed in the crankcase walls allow the passage of coolant and lubrication oil. A knock sensor is located on the left side of the block.
The bedplate (2) is made from die-cast aluminium alloy and has cast iron cast-in bearing caps. The supports and main bearing caps are machined while assembled together with the engine block. Bolts and locating dowels are used to assure precision assembly of the bedplate and engine block. There is a bead of sealant between the bedplate and engine block to prevent oil leaks.
The function of the bedplate is to:
- form the load carrying structure with the engine block
- support the crankshaft
- allow return of the engine lubrication oil to the pan
- support the engine oil pan